This invention relates to molded nuts in general and more particularly to a molded nut which contains a single internal thread.
Nuts such as wing nuts which have typically been made of metal such as steel, brass and aluminum, for certain applications, are now being molded out of plastic materials such as nylon. Heretofore, such nuts have been formed by one of three different methods. A first method comprises molding the nut without threads and then tapping a thread into the molded part. The disadvantage of this method is obvious in that it requires the additional step of tapping. A second method comprises using an unscrewing mold in which the thread is formed by a male-thread member which is then screwed out of the part using hydraulic or mechanical means after molding is completed. This mold, of course, is more complex and requires the additional means to remove the threaded member on completion of molding. The third manner in which internal threads are formed is through the use of a collapsible core during molding. The collapsible core method forms the internal thread using two or more segments of a male member that forms partial threads and then it is collapsed and removed from the molded part. The disadvantage of this molding method, in addition to the need to have means in the mold to collapse and expand the core, is that the threads are only partial.
Thus, from the molding standpoint, the first method, in which a simple mold is used, i.e., where there is no need for means to unscrew a mold or collapse a mold, is the easiest. However, as noted above, it suffers from a disadvantage in that an additional step of tapping is required. Thus, it becomes apparent that if it were possible to mold a threaded nut, such as a wing nut with a simple mold and without the need for further tapping, the overall cost of production of nuts of this type could be substantially reduced.